A document scanner user can create a digital document image by processing an original document parallel to the lens of the document scanner, thereby avoiding any perspective distortion in the document image. A mobile phone user can also create a digital document image using a digital camera incorporated into the mobile phone, but perspective distortion may be created in the document image if the original document is not perfectly parallel to the digital camera lens. For example, if a user takes a digital camera photograph of a paycheck to be electronically deposited in the user's bank account, the user may position the lens of their mobile phone's digital camera such that the lens is not perfectly parallel to the paycheck, thereby creating a perspective distortion in the image of the paycheck despite the user's best efforts to avoid creating such a distortion. Image perspective correction tools can correct some perspective distortions in document images, but user requirements may make using such tools burdensome. For example, an image perspective correction tool may require a user to participate in a time-consuming procedure that identifies all of the corners of a document image in order to correct the perspective distortion. In another example, an image perspective correction tool may require a user to photograph an original document super-imposed over a dark background so that the image perspective tool can more easily identify all of the corners of the document image in order to correct the perspective distortion. Furthermore, such image perspective correction tools may experience difficulties when the background of the original document is not sufficiently dark, when the original document has folded or torn corners, when protruding documents beneath the original document make identification of the original document's corners more difficult, and when notes are attached to the original document.